Development of a High-Linearity Voltage and Current Probe with a Floating Toroidal Coil: Principle, Demonstration,...

Area of Science:

• Plasma physics
• Electrical engineering
• Sensor technology

Background:

• Conventional voltage and current (VI) probes suffer from crosstalk between separate sensors, degrading measurement linearity and accuracy.
• Crosstalk in VI probes is a significant limitation in precise plasma diagnostics and process monitoring applications.

Purpose of the Study:

• To develop and validate a novel VI probe design that eliminates crosstalk by integrating voltage and current sensing capabilities.
• To improve the accuracy and linearity of VI measurements in plasma environments.

Main Methods:

• Proposed a VI probe design incorporating a floating toroidal coil for simultaneous voltage and current sensing.
• Utilized three-dimensional electromagnetic wave simulation to establish the probe's operating principle and optimize its design.
• Fabricated and calibrated the optimized VI probe using a high-voltage probe and a vector network analyzer.
• Compared the performance of the fabricated probe against a commercial VI probe.

Main Results:

• The proposed toroidal coil VI probe effectively eliminated crosstalk, a common issue in conventional designs.
• Electromagnetic simulations guided the optimization of the probe's design for enhanced performance.
• Calibration confirmed accurate root-mean-square (RMS) voltage and current measurements.
• The fabricated probe demonstrated slightly higher linearity (R2=0.9967 for voltage, R2=0.9938 for current) compared to a commercial VI probe.

Conclusions:

• The developed toroidal coil VI probe offers a crosstalk-free solution for accurate plasma diagnostics.
• The probe's enhanced linearity and accuracy make it suitable for demanding plasma process monitoring.
• This innovative VI probe design has the potential to advance measurement capabilities in various scientific and industrial fields.